Implementing energy audits in Vietnamese industrial enterprises

Energy audits in industrial enterprises identify where energy is being used, what can be improved and which measures deserve priority. A useful report must be based on operating data, suitable measurements and verifiable technical and economic analysis.

Preliminary survey versus detailed audit

• Preliminary survey: review bills, output, operating conditions and the site to identify major energy users, obvious losses and additional measurement needs.
• Detailed audit: plan measurements, analyse consumption and efficiency, and calculate improvement options, investment costs and expected benefits.

The depth of the assessment should match its purpose, process characteristics and applicable obligations. A template report using estimated figures should not replace an actual site assessment.

A practical implementation process

1. Agree the scope: define sites, systems, energy types, data periods and deliverables.
2. Collect data: compile bills, output, shift schedules, equipment ratings, energy-supply diagrams and operating changes.
3. Survey and measure: choose representative locations, timing and durations, and record operating conditions to help interpret results.
4. Analyse the baseline: reconcile measurements with overall data and identify significant energy uses and opportunities to reduce losses.
5. Evaluate measures: calculate potential savings, investment and operating costs, process impacts and assumptions.
6. Accept the report and implement: agree the report, priorities, responsibilities and post-implementation monitoring methods.

How should the business participate?

Appoint a technical coordinator who understands the production process and can work with production, maintenance, finance and the consultant. Operators help verify running hours, actual loads and conditions that bills do not show. Missing or inconsistent data should be clarified before conclusions are drawn.

Choosing an energy-audit provider

• Check the organisation's eligibility and published information against the applicable requirements.
• Review personnel, qualifications, experience with the type of facility and the measurement plan.
• Check equipment, calibration status, data-processing methods and deliverables.
• Agree confidentiality, site safety and how findings will be explained and substantiated.

Reference: the Ministry of Industry and Trade's procedures and conditions for energy-audit organisations. Check the current applicable documents for the facility. Penalties and references to Circular 09/2012 in the older article should not be treated as a current legal basis.

Assess technical and economic feasibility together

Measures must suit the load, product quality, safety requirements and overall system. For example, a variable-speed drive should be evaluated against load characteristics, controls and power-quality effects; installing one on every motor does not automatically save energy.

• State energy prices, operating hours and expected savings.
• Calculate investment, maintenance, operating and other associated costs.
• Review payback and, where appropriate, net present value (NPV), internal rate of return (IRR) and sensitivity.
• Set investment criteria according to company policy and project risk; a payback below five years is not a universal mandatory condition.

Accepting the report and measuring improvement results

Report acceptance should involve representatives of energy-using departments. Check data sources, calculation methods, feasibility and the action plan. After implementation, compare consumption on an equivalent operating basis and consider changes in output, weather and running hours before attributing all differences to the saving measure.